There's no such thing like definite and indefinite articles in Russian. What you actually asking essentially is "how come up with two different sentences so there will be one-to-one correspondence between such sentences and usage of definite and indefinite articles". But if you'll think about it you'll realize that that will mean that, well, there are definite and indefinite articles in Russian and, thus, we came to contradiction.
It's like asking "Hey, in our language we have exclusive and inclusive
we - how it supposed to be expressed in your language?". The thing is if the concept doesn't exist you can not have single way to do it.
In some cases
какой-то would be a fit. In some cases
этот. In some - quite small set of cases -
один can be used ("один человек когда-то мне сказал" differs from "человек мне когда-то сказал".
But generally speaking this concept just does not belong to Russian. In other words, "I saw a house" depending on context can be translated "] увидел какой-то дом", "я вижу какой-то дом", "я вижу дом" etc. while "I saw the house" can be translated as "я вижу тот самый дом", "я вижу дом", "я вижу этот дом" etc.